Is such a captcha AI-resistant?
Well to give you a short answer, I would say that YES, it would be MORE resistant than a more standard captcha approach...
This being said, I would still go as far as to predict something like a 75-80% successful prediction rates, for a custom model which is designed specifically for defeating a mechanism such as what you describe. The reason why I am fairly confident in such an appraisal, is primarily because of the following:

New techniques which researchers have begun to explore, which are intended to be &quot;Structure Preserving Convolutions&quot; which utilize a higher dimensional filter to store the extra correlation data.

I think that the obfuscation efforts that you mention will definitely help to some degree, although they can be easily defeated by training the model on a dataset which you pull out some portion of the samples during pre-processing and inject the same sort of noise and glitch treatments, etc.

An idea that would be worth exploring would be to process your dataset with an adversarial model which you could then use to generate Adversarial Noise that could then be fed into a pre-process step for your images and replace (or extend) the obfuscation efforts!




TL;DR: If you cant beat 'em, then join 'em! Just train a model to defeat your captcha implementation, and then use the model to generate adversarial examples and then apply obfuscations to your data set accordingly!
For more information on what I am talking about in my suggestion for further obfuscation efforts explore some of the papers you can find on Google Scholar - Ensemble Adversarial Training Examples